How to use the rpg.command.Command function in rpg

"RPG is tool, that guides people through"
            "the creation of a RPM package. RPG makes packaging much easier"
            "due to the automatic analysis of packaged files. Beginners can"
            "get familiar with packaging process or the advanced users can"
            "use our tool for a quick creation of a package.")
        self.base.spec.URL = "https://github.com/rh-lab-q/rpg"
        self.base.target_arch = "x86_64"
        self.base.target_distro = "fedora-22"
        self.base.spec.Requires.update(['makedepend', 'mock'])
        self.base.spec.BuildRequires.update(['makedepend',
                                             'mock',
                                             'python3-nose'])
        self.base.fetch_repos(self.base.target_distro, self.base.target_arch)
        self.base.run_extracted_source_analysis()
        self.base.run_patched_source_analysis()
        self.base.spec.check = Command(["make test-unit"])
        self.base.build_project()
        self.base.run_compiled_source_analysis()
        self.base.install_project()
        self.base.run_installed_source_analysis()
        self.base.build_srpm()
        self.assertTrue(self.base.srpm_path.exists())
        self.base.build_rpm_recover(
            self.base.target_distro, self.base.target_arch)
        self.assertTrue(self.base.rpm_path)

def md5Tar(self, t):
        mdsum = Command(
            "tar --list -f " + path_to_str(t) + " 2>/dev/null | "
            "awk -F/ '{ if($NF != \"\") print $NF }' | "
            r'sed -e "s/.*\///gm" | sort | md5sum'
        ).execute()
        self.assertNotEqual(self.FNF_MD5, mdsum)
        return mdsum

def test_new_line(self):
        cmd = Command("a\nb\n")
        self.assertEqual("a\nb", str(cmd))

def build_srpm(spec_file, tarball, output_dir):
        """ Builds source rpm from spec and tarball and moves it to the
            output directory """
        Command("rpmdev-setuptree").execute()
        Command("cp " + path_to_str(tarball) +
                ' $(rpm --eval "%{_topdir}")/SOURCES').execute()
        output = Command("rpmbuild -bs " + path_to_str(spec_file)).execute()
        Command("mv " + path_to_str(output.split()[-1]) +
                " " + path_to_str(output_dir)).execute()

def validatePage(self):
        self.base.spec.install = Command(self.installEdit.toPlainText())
        self.base.spec.pretrans = Command(self.pretransEdit.toPlainText())
        self.base.spec.pre = Command(self.preEdit.toPlainText())
        self.base.spec.post = Command(self.postEdit.toPlainText())
        self.base.install_project()
        self.base.run_installed_source_analysis()
        return True

self.package = ""  #: initial value: ""
        self.description = ""  #: initial value: ""
        self.BuildRequires = set()  #: initial value: set()
        self.Requires = set()  #: initial value: set()
        self.Provides = set()  #: initial value: set()
        self.files = set()  #: initial value: []
        self.changelog = []  #: initial value: []
        self.prep = Command()  #: initial value: Command()
        self.build = Command()  #: initial value: Command()
        self.pre = Command()  #: initial value: Command()
        self.install = Command()  #: initial value: Command()
        self.check = Command()  #: initial value: Command()
        self.post = Command()  #: initial value: Command()
        self.preun = Command()  #: initial value: Command()
        self.postun = Command()  #: initial value: Command()
        self.pretrans = Command()  #: initial value: Command()
        self.posttrans = Command()  #: initial value: Command()
        self.clean = Command()  #: initial value: Command()

        # list of generated translation files
        self.files_translations = []

        # (Build)Required file list that will be traslated into packages
        self.build_required_files = set()
        self.required_files = set()

self.Vendor = ""  #: initial value: ""
        self.Packager = ""  #: initial value: ""
        self.package = ""  #: initial value: ""
        self.description = ""  #: initial value: ""
        self.BuildRequires = set()  #: initial value: set()
        self.Requires = set()  #: initial value: set()
        self.Provides = set()  #: initial value: set()
        self.files = set()  #: initial value: []
        self.changelog = []  #: initial value: []
        self.prep = Command()  #: initial value: Command()
        self.build = Command()  #: initial value: Command()
        self.pre = Command()  #: initial value: Command()
        self.install = Command()  #: initial value: Command()
        self.check = Command()  #: initial value: Command()
        self.post = Command()  #: initial value: Command()
        self.preun = Command()  #: initial value: Command()
        self.postun = Command()  #: initial value: Command()
        self.pretrans = Command()  #: initial value: Command()
        self.posttrans = Command()  #: initial value: Command()
        self.clean = Command()  #: initial value: Command()

        # list of generated translation files
        self.files_translations = []

        # (Build)Required file list that will be traslated into packages
        self.build_required_files = set()
        self.required_files = set()

def validatePage(self):
        self.base.spec.postun = Command(self.postunEdit.toPlainText())
        self.base.spec.preun = Command(self.preunEdit.toPlainText())
        self.base.spec.posttrans = Command(self.posttransEdit.toPlainText())
        self.base.write_spec()
        return True

self.Obsoletes = ""  #: initial value: ""
        self.Conflicts = ""  #: initial value: ""
        self.Vendor = ""  #: initial value: ""
        self.Packager = ""  #: initial value: ""
        self.package = ""  #: initial value: ""
        self.description = ""  #: initial value: ""
        self.BuildRequires = set()  #: initial value: set()
        self.Requires = set()  #: initial value: set()
        self.Provides = set()  #: initial value: set()
        self.files = set()  #: initial value: []
        self.changelog = []  #: initial value: []
        self.prep = Command()  #: initial value: Command()
        self.build = Command()  #: initial value: Command()
        self.pre = Command()  #: initial value: Command()
        self.install = Command()  #: initial value: Command()
        self.check = Command()  #: initial value: Command()
        self.post = Command()  #: initial value: Command()
        self.preun = Command()  #: initial value: Command()
        self.postun = Command()  #: initial value: Command()
        self.pretrans = Command()  #: initial value: Command()
        self.posttrans = Command()  #: initial value: Command()
        self.clean = Command()  #: initial value: Command()

        # list of generated translation files
        self.files_translations = []

        # (Build)Required file list that will be traslated into packages
        self.build_required_files = set()
        self.required_files = set()